Abstract: In Huabei Oilfield, oil reservoirs are deep, the temperature of water injection wells is high and inter-layer water injection pressure difference is large, which seriously restrict the development of current separate-layer water injection technologies. To solve the contradiction between current separate-layer water injection process and production demand, this paper researched a new generation of separate-layer water injection technology by taking the external cable-controlled intelligent separate-layer water injection technology as the main part. The key indicators (e.g. temperature tolerance and pressure bearing capacity) of electric intelligent water flow regulator are improved by optimizing the design of downhole intelligent water flow regulator. Based on the multi-level and multi-stage separate-layer water injection technology for deep deviated wells, a series of cable-controlled intelligent separate-layer water injection tools are developed, such as through-cable cover protection packer and through-cable successive unsetting packer, and thus the reliability of downhole tools is improved significantly and the construction success ratio is increased up to 100%. This technology fundamentally changes the measurement and regulation mode of separate-layer water injection well, which can control the detection, setting, measurement and regulation of separate-layer water injection well remotely without any testing vehicles and operation staff on site, so as to reduce the production cost. The functions of automatic interval injection rate regulation, real-time production performance monitoring and remote interval water flow regulation provide data and technological support for fine reservoir analysis and dynamic production adjustment, realize effective water injection and fine water injection, and are beneficial to the improvement of waterflooding development effect.